Drive transmission



Sap; 7, 1940. M A H PF 2,215,103

DRIVE TRANSMISSION Filed June 6, 1959 Patented Sept. 17, 1940 UNI-TED STATES PATENT OFFICE 2,215,103 DRIVE TRANSMISSION Marcus A. Holpfer, Ccraopolis, Pa.

Application June 6, 1939, Serial No. 277,642

2 Claims.

This invention relates to a fluid controlled device transmission primarily designed and intended for use in connection with the forward drive mechanism'of a motor vehicle, but it is obvious that ,the device may be employed in any other type of apparatus or for any other purposes wherein it is found to be applicable.

- Important objectsand advantages of the invention are to provide a driveltransmission of 10. the character described, which is hydraulically controlled, which does not require a separate clutch structure to effect its successful operation, which is quietly, positively and automatically operable for: transmitting change-speed driv- 15. ing power, which. is simple in its construction and arrangement, compact, and comparatively economical in its manufacture, installation, operation and maintenance.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the novel construction, combination and arrangement of parts herein specifically described and illustrated in the accompanying drawing, but it is to be understood 25 that the latter is merely illustrative of an embodiment of the invention, and that the actual needs of practice and manufacture may require certain mechanical variations from the embodiment shownr It is, therefore, not intended to limit the invention to the disclosure thereof herein illustrated, but rather to define such limitations to the scope of the claims hereunto appended.

In the drawing wherein like numerals of ref- ,5 erence designate corresponding parts throughout the several views:

f Figure Us a longitudinal cross section view of a drive transmission constructed in accordance with the invention.

Figure 2 is a front end view of the casing structure with the front end plate removed from the latter.

' Figure 3 is a transverse sectional View on line I 3-3, Figure 1.

Figure 4 is a transverse cross sectional view of one of the plungers embodied in the present invention.

Referring in detail to the drawing l denotes an elongated, cylindrical casing including a rear 5 end plate 2 secured thereto by bolts 3, and a front end plate 4 secured thereto by bolts 5. The interior of the casing is formed with a thick, transversely extending wall 6, which latter provides a plunger chamber 1 disposed for- 55 wardly thereof, a fluid supply chamber 8 disposed rearwardly thereof, and compression chamber 9 disposed in said wall at the rear end thereof.

The casing wall 6 is formed to provide a plurality of cylinders it]. The latter are disposed longitudinally in parallel relation to each other, and the front ends thereof open into the plunger chamber 1. A plunger II is shiftably mounted for longitudinal, reciprocal movement in each of the cylinders. The length of the plungers is greater than the depth of the cylinders, whereby even when said plungers are in'the furthermost rearward discharging positions, the forward end portions thereof will project into the plunger chamber.

A driven shaft I2 is formed integral with or otherwise suitably secured to the rear end plate 2, and a driving shaft l3 operated by an internal combustion engine or other apparatus providing the prime source of power, extends into the easing, and is suitably journaled for rotation in the front end plate 4 by a suitable stuffing box and packing gland M, and in forward end of the casing wall 6, as indicated at I5. The shafts l2 and I3 are longitudinally aligned relatively to each other and have a common axis with the axis of the cylindrical casing.

The driving shaft I3 is formed with an enlarged cylindrical portion 16, which may be formed integral with the former or fixed thereto in any suitable manner. The shaft portion 16 is disposed within the plunger chamber 1, of the casing, and is preferably commensurate to the length of said plunger chamber. An outwardly projecting annular cam Il' surrounds and is formed integral with the periphery of the shaft portion It. The cam engages in suitable transversely extending grooves l8, which latter are formed on the inner sides of the projecting forward end portions of respective plungers H with-- in the plunger chamber 1. It will be apparent that the rotation of the annular cam I! will impart longitudinal, reciprocal movement to all of the engaged plungers in respective cylinders i0.

The operation of the drive transmission involves the use of liquid in the form of oil or any other suitable fluid. The plunger chamber 1, the supply chamber 8, and the compression chamber 9 are completely filled with the operating fluid, and the latter may be placed in the casing or drained therefrom through a plugged aperture [9 suitably located in the casing.

The plunger chamber 1 and the supply chamber 8 are communicably joined. by passages 20 extending through the casing wall 6. The rear closed end of each of the cylinders ll communicates with the supply chamber 8 by a passage controlled by a comparatively large capacity intake valve element 2|, and with the compression chamber 9 by a passage controlled by a relatively small exhaust valve element 22. The valve elements 2| and 22 are preferably spring controlled ball type, of the usual construction, and function automatically for the purposes employed.

As clearly illustrated in Figure 1, the forward or suction stroke of each of the plungers will open the intake valve element 2| to allow the entrance of the operating fluid from the supply chamber 8 to the cylinder in, while the associated exhaust valve element 22 will be held in the closed position preventing the entrance of the fluid from the cylinder to the compression chamber 9.

The rearward or discharge stroke of each of the plungers l will close the intake valve element 2| to prevent entrance of the fluid from the cylinder to the supply chamber 8, while the associated discharge valve element 22 will be opened to allow the passages of the fluid from the cylinder to the compression chamber 9. Thus, it will be evident that at each reciprocal stroke of the plungers, the operating fluid will be drawn from the supply compartment 8 and discharged in to the compression chamber 9.

An enlongated needle valve 23 is mounted and longitudinally shiftable in the driving shaft I3 and projects rearwardly from the rear end of the latter into the compression chamber 9. The shiftable movement of the needle valve 23 is limited by a cross pin 24, which latter is fixed adjacent to the front end of said needle valve and engaged in a pair of opposed slots 25 formed in driving shaft l3. The ends of the cross pin are fixed in a slide collar 26 longitudinally shiftable on the driving shaft but revoluble with the latter.

A seating plug 28 is threadedly secured to the rear side of the casing wall 6 and provides the rear wall for the compression chamber 9. The plug 28 has a centrally disposed seating passage 29 providing communication between the compression chamber 9 and the supply chamber 8. The rear free end of the needle valve 23 is tapered and adapted for seating in said passage 29 for opening or closing the latter during the operation of the device in the manner and for the purposes to be described.

A piston 39 is mounted in a cylinder 3| formed in the rear end plate 2 and carries a fixed forwardly projecting push rod 32. The latter and said piston 3|) extend into the supply chamber 8 and are longitudinally aligned with the needle valve 23, and the free end of said push rod extends into the passage 29 and is always seated against the free tapered end of the needle valve, as shown in Figure 1. A spiral spring 33 is mounted in a pocket provided therefor in the driven shaft I2 and normally functions to force the piston 39 forwardly in the cylinder 3| to maintain the engagement of the push rod 32 against the needle valve 23.

When the piston is .in its furthermost rearward position in the cylinder 3|, the forward end thereof projects from the open forward end of the latter and projects into the supply chamber '1. A transversely extending cross passage 36 is formed in said projecting end of the piston and communicates with the through passage in the piston, which latter passage is controlled by an intake valve element 35 of'the spring controlled ball type. During the forward movement of the piston 30 in the cylinder 3|, the valve element 35 opens to allow the operating fluid to enter said. cylinder through the piston, but the rearward movement of the piston into its cylinder closes the valve element 35 and slowly forces the'fiuid from the cylinder through a relatively small passage 36 in the piston into the cross passage 34 and through the latter into the supply chamber 3. The purpose of forcing the fluid through the small passage 38 is to retard the return movement of the piston 30 from its fully projected position in the cylinder 3i during the operation of the device in the manner to be described.

The needle valve 23 is regulated and controlled by the operation of a governor attachment comprising a plurality of suitable centrifugally actuated weights 3?. Each of the latter is pivotally connected and carried by a suitable support 38 fixedly secured to the front end plate 4.

The weights 3? are engaged in an annular groove 39, formed in the slide collar 26, in a manner, when extended, to shift the latter on the driving shaft l3 toward the casing to thereby:

force the needle valve 23, connected to said slide collar by the cross pin 24,'to the closed position by the engagement of the tapered free end thereof in the seating passage 29.

A spiral spring 39 is mounted on the driving shaft l3 with one end abutting against the rear face of the slide collar 26, and with the other end thereof abutting against an adjusting ring 38. The latter surrounds the driving shaft, and,

is threadedly engaged in the packing gland M. The ring 40 is adjustable to adjust the tension of the spring 39, and the latter. normally functions to shift the slide collar 26 forwardly on the driving shaft to shift and normally maintain the needle valve 23 in the open position from its engagement in the seating passage 29.

To shift the needle valve 23 to the open or inoperative position against the centrifugal acv tion of the weights 3? while the latterare operating to close said needle valve in the manner set forth, a manually operated control mech-' anism is provided. The latter comprises a pedal- 8 which is suitably supported and pivoted to the equipped vehicle structure 42. The pedal is further pivotally connected to a slotted slide bar 43 longitudinally slidable in the vehicle structure.

and carrying a pair of spaced depending lugs M, which engage the peripheral edge margin of an annular flange 45 formed integral with the slide collar 36. A hand operated lever 46, pivotally connected with the slotted slide bar, and with the vehicle structure, is likewise operable for shifting the needle valve to the open position.

The lever 46 is associated with a spring controlled latch 48 and a notched quadrant 49 for securing when necessary, the needle valve in the open, inoperative position during the operation or rotation of the driving shaft l3. A spring 50-, connecting with the vehicle structure 42 and with the slide bar 45, normally functions to re-v turn and hold the latter in the inoperative'position, as shown in Figure 1. Unless the lever 46 is secured in the inoperative position, the construction, arrangement, and operation of the slotted slide bar and of associated parts, anew the operation of the pedal Mindependentlyof the lever 46, or the operation of the latter in-; dependently of the pedal or the automatic con-' trol of the needle valve 23 by the operation of 15" the centrifugally actuated weights 3'I independently of either the pedal or the released lever.

I In practice the operation of the improved fluid controlled drive transmission is as followsz-Assuming the apparatus employed for driving a motorvehicle equipped therewith, the operator sets the lever 46 in the released position, Which'latter is shown in Figure 1. As the spring 39 normally holds the slide collar 26 in the forward position the needle valve 23 is thereby held in the open position, being disengaged from the seating passage 29.

At idling speed of the vehicle engine, the governor weights 31 will not be actuated to extend the latter sufliciently to shift the needle valve 23 to the closed position, and while the engine or driving shaft I3 is rotating at such idling speed the driven shaft I2 will not be revolved, as the plungers II will be operating to simply circulate the fluid from the supply chamber 8 through the compression chamber 9 back into the supply chamber.

When the driving shaft I3 is rotating at idling speeds, the liquid flow, occasioned by the reciprocation of the pistons II by the cam H on the driving shaft I3, will not be sufficiently resisted to impart any rotation to the casing I. As the speed of the driving shaft I3 is increased a resistance to liquid flow, due to restricted size of the passages to the chamber 9, will obtain, thereby causing initial rotation of the casing I. As casing I picks up in speed the weights 31, under the influence of centrifugal force, will be actuated to move the needle valve 23 toward its closed position against the action of the spring 39 and the operation of the piston 30, thereby tending to cause the casing I with the driven shaft I2 to rotate with the driving shaft I3.

During the protracted movement of the needle valve 23 to the closed position the driving shaft I3 is permitted to rotate at a greater speed than the casing and driven shaft I2 due to the forced discharging fluid escaping from the compression chamber 9 through the seating passage 29. The tendency of the casing and driven shaft to rotate during the retarded movement of the needle valve will gradually increase until the driving force of the driving shaft is sufficient to actually impart reduced speed rotation to the entire casing and the driven shaft, and thus provide the initial starting impetus and subsequent starting propulsion of the driven shaft.

After the needle valve 23 has been shifted to the fully closed position, the fluid can no longer escape through the seating passage 29, and in consequence the casing and the driven shaft I2 will rotate with the driving shaft I3 and establish the direct driving connection between the latter and the driven shaft.

If the driven shaft I2 is overloaded for the direct operation of the driving shaft I3, the reduced speed thereof will cause the contraction of the governor weight 31 by the action of the spring 39, and thereby automatically shift the needle valve to the open position, when again the varied speeds of respective shafts will be effected to drive the driven shaft at the necessary low and intermediate speeds required to again establish the direct drive of the driving and driven shafts.

While my improved transmission will function to rotate in either direction, the transmission does not provide for the separate reverse rotation of the driven shaft I2, as such reverse mechanism forms no essential part of the present disclosure, but it is evident that some suitable reverse mechanism 3 may be successfully embodied in the improved transmissionwithout departing from the principle of the invention. 7

The Present invention provides a most durable and efiicient device of its kind, which is entirely automatic in, itsoperati'on, ;and which maybe successfully employed to operate a shaft at any speed to provide the power necessary to effect the start, propulsion, or operation of the apparatus it is intended to operate.

What I claim is:

1. In a fluid controlled drive transmission for a power apparatus, the combination of a casing formed with a transversely extending wall providing a fluid supply chamber, a plunger chamber and a fluid compression chamber, a plurality of longitudinally disposed cylinders formed in said Wall and opening into said plunger chamber, a plunger mounted in each of said cylinders and projecting into said plunger chamber, a driven shaft fixed to said casing, a driving shaftrevolubly engaged in said casing and being aligned with said driven shaft, a valve element mounted and longitudinally shiftable in said driving shaft, an annular cam carried by and surrounding said driving shaft and engaging in grooves at the inner sides of said plungers for imparting reciprocal movement to the latter for drawing the fluid from said suppl chamber and for forcing thefluid into the compression chamber, and centrifugally actuated means carried by said casing operable for shifting said valve element for controlling the passage of the fluid from said compression chamber to said supply chamber to confine the fluid in said compression chamber and thereby causing the rotation of said casing and of said driven shaft with said driving shaft.

.2. A fluid controlled drive transmission comprising an elongated cylindrical casing including a front end plate and a rear end plate, a transversely disposed wall formed integral with said casing and providing the interior of the latter with a fluid supply chamber, a plunger chamber and a fluid compression chamber, a driven shaft fixed to said rear end plates, a driving shaft journaled for rotation in said front end plate and in said wall, a plurality of longitudinally extending cylinders formed in said wall and opening into said plunger chamber, a plunger mounted for reciprocal movement in each of said cylinders and projecting into said plunger chamber, a transversely extending groove formed in the inner side of the projecting end of each of said plungers, a comparatively large capacity intake valve element automatically operable for controlling the entrance of the fluid from said supply chamber to respective cylinders, a comparatively small capacity discharge valve element for automatically controlling the discharge of fluid from respective cylinders to said compression chamber, the rear wall of said compression chamber being provided with a seating passage, a. needle valve mounted and longitudinally shiftable in said driving shaft and projecting into said compression chamber and being shiftable to open or close said seating passage, an annular cam fixed to and extending around said driving shaft, said cam engaging in said grooves and being operable for imparting longitudinal reciprocal movement to said plungers for drawing the fluid from said supply chamber through said intake valve elements to said cylinders and for discharging fluid from said cylinder through said discharge valve elements, a slide collar mounted and longitudinally shiftable on said shaft and being con- 75 nected with said needle valve, resilient means mounted on said driving shaft and engaging said collar for shifting said needle valve to the open position, centrifugally actuated means carried by said casing and engaging said collar automatically operable for shifting said needle valve to the closed position, means for retarding the movement of saidneedle valve to the closed position, and manually operated means for shifting the needle valve to the open position and for securing the latter in the open position.

MARCUS A. HOLPFER. 

